In 1984, while completing my undergraduate degree, I took electives titled “China Today”, “Russian Literature,” and “International Terrorism.” I lay no claim to deep expertise in any of them, but at the time, the terrorism course proved the most compelling. It was a full classroom with bright, sometimes sleepy faces — an atmosphere abruptly interrupted several weeks into the term.

One day, two classmates wearing backpacks walked in late, brandished pink water pistols, and announced that if everyone cooperated, nobody would get hurt. One held his water pistol to the professor’s head while the professor, surprised but fully participating in the unsanctioned exercise, pleaded with the class to comply. The other guarded the door.